Sample Tube Research Articles

Prediction of Ovarian Cancer with Deep Machine Learning and Alternative Splicing

Objective: Early detection of ovarian cancer could lead to improved survival rates, however no method has reliably been able to predict ovarian cancer. The aim of this study is to determine if processing alternative splicing data from high grade serous ovarian cancer patients using machine learning analytics will discriminate high grade serous ovarian cancer from normal fallopian tube samples. The ultimate goal would be to have a model that can predict high grade serous ovarian cancer with a blood test. Methods: This is a case-control study of patients with confirmed high grade serous ovarian cancer and those undergoing salpingectomy for benign indications. RNA-sequencing was performed on all samples. RNA-sequence data was then put into Deep-learning augmented RNA-seq analysis of transcript splicing software suite. Deep-learning augmented RNA-seq analysis of transcript splicing created a model of differential alternative splicing aimed to discriminate between high grade serous ovarian cancer and normal fallopian tube. DEXSeq analysis was used to determine exon-based expression. Initial results with both analytics were then modelled with multivariate lasso regression to create prediction models (performance determined by area under the curve and 95% CI). Models created were the validated using The Cancer Genome Atlas data sets. Results: One hundred and twelve high grade serous ovarian cancer and 12 benign samples were successfully sequenced. Deep-learning augmented RNA-sequencing analysis of transcript splicing identified 998 unique differentially expressed exons between high grade serous ovarian cancer and controls. Multivariate lasso regression analysis identified several exons that predicted high grade serous ovarian cancer with high performance. Specifically, ENSG00000182512:E001 from gene GLRX5 was highly predictive of high grade serous ovarian cancer with an area under the curve of 100%. Conclusions: Application of machine learning analytics to exon differential expression, most likely due to alternative splicing, predicted high grade serous ovarian cancer with high performance. These results were validated in an independent dataset of cases and controls. Differential exon expression from cell-free RNA potentially could be used for early diagnosis of high grade serous ovarian cancer.

Design of a three-loop asymmetric coil producing a homogeneous radiofrequency B1 field gradient along the axis of a vertical sample tube

A coil system generating a vertical radio-frequency (rf) field gradient (B1 gradient) has been built for surrounding, in a horizontal magnet, a vertical sample (object) of axial symmetry. The system comprises three coaxial loops with an overall shape either spherical or ellipsoidal. The geometry has been theoretically and experimentally devised for producing a very uniform gradient (cancellation of B1 derivatives from second order up to sixth order) in the central region where a vertical receiver/transmitter coil is installed. The latter is of the saddle-shaped type and is geometrically and electrically decoupled from the gradient coil system. This receiver/transmitter coil not only ensures an optimal signal reception but, in addition, is able to deliver perfectly homogeneous rf hard pulses which are mandatory in most NMR experiments. In its present design, the system delivers a uniform gradient in a limited region but could be extended at will. Its main advantages over static field gradients (B0 gradients) appear clearly in the case of very short transverse relaxation times. This property has been emphasized in the case of experiments leading to the measurement of diffusion coefficients. Also, this system would be suitable for chemical shift imaging (CSI) experiments as confirmed by a preliminary test experiment.

Experimental Study of Hydroformed Al6061T4 Elliptical Tube Samples under Different Internal Pressures

In order to achieve crack free elliptical shape under controlled conditions, an experimental set-up was designed and fabricated. This setup consists of three hydraulic cylinders, an intensifier, a hydraulic power pack, storage tanks, forming die, and all parts are controlled by a Programmable Logic Controller (PLC) system. The elliptical samples can be achieved through proper control of internal pressure and axial force with proper sealing. Experimental work has been carried out with different magnitudes of internal pressure and constrained conditions of axial force. Initially die of elliptical shape has been designed and modeled in Abaqus to successfully achieve the particular shape of the Al6061T4 tube under different internal pressure. The fabricated tube hydroforming machine set-up is highly effective for forming 0.5 mm-2 mm thick Al6061T4 alloy tube samples. The Experimental test has been carried out at 12.7 mm outer diameter, 175 mm length and 0.5 mm thick Al6061T4 samples. Bulge height parameters measured at different points of regular distance gap on the axial direction of the tube length and corner radius found at different pressures range of the samples are plotted under different internal pressures. Samples having an 18.7 mm major elliptical bulge were achieved during the experiment. The experimental data was validated by simulation results.

Using Residual Blood from the Arterial Blood Gas Test to Perform Therapeutic Drug Monitoring of Vancomycin: An Example of Good Clinical Practice Moving towards a Sustainable Intensive Care Unit.

Regarding sustainability in the intensive care unit (ICU), there is increasing interest in reducing material waste and avoiding unnecessary procedures. Therapeutic drug monitoring (TDM) of vancomycin, using a dedicated tube, is standard clinical care during treatment with vancomycin. Furthermore, in the ICU, on a daily basis, arterial blood gas (ABG) tests are frequently performed throughout the day. After analysis, a variable volume of blood is discarded. Lithium heparin (LiHep) syringes for ABG tests differ from normally used dipotassium ethylenediaminetetraacetic acid (K2EDTA) tubes. The primary objective was to compare both containers and validate the use of LiHep syringes. Secondary objectives were to evaluate the potential impact on saving materials, nursing time, and costs when implementing vancomycin TDM via LiHep syringes. Vancomycin analysis from sampling in lithium heparin (LiHep) syringes for ABG tests was validated and compared with the concentrations from conventional sampling in K2EDTA tubes. For method comparison, a Bland-Altman plot and Deming regression analysis were performed. The method was validated for inter- and intra-day precision and accuracy. Vancomycin was analyzed by means of the validated method using a particle-enhanced turbidimetric inhibition immunoassay (PETINIA) autoanalyzer. Furthermore, an analysis was conducted to evaluate the potential impact of implementing vancomycin sampling via ABG tests on savings in materials, nursing time, and costs. From 18 patients, 24 plasma samples in both K2EDTA tubes and LiHep syringes were obtained and compared. The mean relative difference between the two containers was -2.0% (-3.0 to -0.93%). Both the Deming regression analysis and the Bland-Altman plot met the acceptance criteria. Potentially, over 1000 blood draws and accompanying materials and packaging can be saved when vancomycin samples are obtained by means of scavenged LiHep syringes. The vancomycin analysis for LiHep syringes showed a total interday precision of 1.95% and an accuracy of 99.7%. The total intraday precision was 2.22%, and the accuracy was 99.2%. Accuracy and precision values were within the acceptance criteria of recovery 85 to 115% and ≤15%, respectively. No significant differences were found in vancomycin concentration between the two analyses, and the LiHep analysis was validated for further implementation in clinical care. Residual blood from ABG test samples can be used for TDM of vancomycin, resulting in a potential reduction of materials used and the number of blood draws. These results will contribute to a more sustainable TDM process with benefits for the patient.

Synthesis of N-Doped Few-Layer Graphene through Shock-Induced Carbon Fixation from CO2.

In this study, graphene and N-doped graphene nanosheets were synthesized through the shock-induced reduction of CO2 using a cylindrical shock-loading apparatus. The mixture of solid CO2 and Mg powder was filled in the pre-cooled sample tube and then impacted by a shock-driven cylindrical flyer tube. The impact generated a shockwave that propagated into the mixed precursor, inducing a chemical reaction between CO2 and Mg at a high shock pressure and high shock temperature. The recovered black powders were characterized via various techniques, confirming the presences of few-layer graphene. The mechanism is carefully shown to be that CO2 was reduced by Mg to form few-layer graphene under shock-induced high pressure and high temperature. By adding carbamide as an N source, this synthetic route was also applied to synthesize N-doped graphene nanosheets. Moreover, the yield and mass of the graphene materials in this study are up to 40% and 0.5 g, respectively. This study showed an efficient and easy-to-scale-up route to prepare few-layer graphene and N-doped few-layer graphene through shock synthesis.

Characterization of aerosols generated by high-power electronic nicotine delivery systems (ENDS): Influence of atomizer, temperature and PG:VG ratios.

The aerosol characteristics of electronic nicotine delivery systems (ENDS) are important parameters in predicting health outcomes since parameters such as aerosol particle size correlate strongly to aerosol delivery and deposition efficiency. However, many studies to date do not account for aerosol aging, which may affect the measurement of ultra-fine particles that typically coagulate or agglomerate during puff development. To reduce aerosol aging, we herein present a unique instrumentation method that combines a) positive pressure ENDS activation and sample collection, b) minimization of both sample tubing length and dilution factors, and c) a high-resolution, electrical low-pressure impactor. This novel approach was applied to systematically investigate the effects of coil design, coil temperature, and propylene glycol to vegetable glycerol ratios on aerosol characteristics including aerosol mass generation, aerosol count generation, and the mass and count size distributions for a high-powered ENDS. Aerosol count measurements revealed high concentrations of ultra-fine particles compared to fine and coarse particles at 200°C, while aerosol mass measurements showed an increase in the overall aerosol mass of fine and coarse particles with increases in temperature and decreases in propylene glycol content. These results provide a better understanding on how various ENDS design parameters affect aerosol characteristics and highlight the need for further research to identify the design parameters that most impact ultra-fine particle generation.

EXPERIMENTAL STUDY OF ELEMENTARY ACTS OF HYDRODYNAMICS AND HEAT TRANSFER DURING THE INTERACTION BETWEEN WATER DROPS AND FILM AND CASTING ROLLER SURFACE

Experimental studies of the boundary conditions of heat transfer for the thermally stressed state of casting rollers while are spraying with flat-jet nozzles in a thermal preconditioning unit have been carried out.
 It is shown that the hydrodynamic conditions on the sprinkling surface are formed as a result of both the influx of "primary" dispersed water from the flat jet nozzle, and the "secondary" liquid coming from neighboring areas in the form of reflected drops and films.
 The heat transfer effecting individual factors that form the hydrodynamic conditions on the sprinkling surface was studied separately.
 The heat transfer intensity was studied depending on the spraying density, the injection-pressure drop and the temperature of the cooled surface when the "primary" drop flow runs in the heat exchange surface. The local sprinkling density of droplets on the surface under the flat-jet nozzle spray were measured using a sampling tube moved by a coordinator. At the same time, the ingress of “secondary” liquid into it was excluded.
 The specific heat flux and heat transfer coefficient were determined using a heat meter made of a nichrome tape heated by direct current. In this case, the isothermality of the surface of the measuring section was ensured. Thermocouples measured the temperature of the lower surface of the tape, and then the stationary temperature of the upper surface of the heat meter sprinkled with drops is calculated.
 As a result of the multivariate analysis of the experimental data, the correlation dependence of the heat transfer coefficient in dependance on the local spraying conditions of the heat meter surface was obtained.
 Also, studies of the heat transfer during water film flow over the heat meter surface were carried out. A similar situation takes place when water spreads between the adjacent nozzles sprinkling zones of the roller surface.
 The correlation dependence between the heat transfer coefficient, the water film speed and the cooled surface temperature was obtained.
 Studies of heat transfer during combined influence of moving water film and a flat-jet nozzle drop flow on the heat exchange surface showed that the heat transfer rate is approximately 80–90 % of the arithmetic sum of the coefficients obtained by separate cooling the heat meter with drops and a water film.

Design and Optimization of Multipoint Sampler for Seafloor Sediment Carried by a Deep-Sea Landing Vehicle

The present study proposes a low-energy consumption multipoint sampler carried by a deep-sea landing vehicle (DSLV) to meet the requirements of time series sampling in local areas and location series sampling in wide areas, and an optimization method of sampling structure based on least-squares support-vector machine (LSSVM) surrogate model and a multi-objective particle swarm optimization (MOPSO) algorithm. First, the overall structure and core components, such as the multipoint sampler’s sampling structure, were designed. The optimization variables were the cone angle, sampling tube inner diameter, and sampling tube inner hole length, which were determined by considering the force with which the sampling structure penetrates the seafloor sediment. Then, the sampling process was simulated by the finite element method-smoothed particle hydrodynamics (FEM-SPH) method, while the accurate LSSVM model of force required for sampling and sampling tube volume was established. Finally, the MOPSO algorithm was used for multi-objective optimization of model parameters of sampling structure. The optimal model of sampling structure that can provide theoretical support for the optimal design of multipoint sampler effectively reduces energy consumption and improves sampling efficiency by force required for sampling 25.89% lower and sampling tube volume 34.81% higher than the original model.

On-site leakage locating of underground natural gas pipeline based on Ne tracer by miniature time-of-flight mass spectrometry

Natural gas pipeline leakage seriously endangers people's lives and properties, and there is an urgent need for on-site, rapid, and accurate locating the leakage point of the underground natural gas pipeline. Here, we added neon gas to natural gas pipelines as a tracer gas, and used a miniature time-of-flight mass spectrometry (mini-TOFMS) to on-site detect neon gas to quickly locate the leak point of underground natural gas pipelines. The mini-TOFMS used capillary tube sampling to directly analyze the leaked neon gas without sample preparation, and the analysis time of a single sample was only 60 s, which was less than one-seventeenth that of traditional off-line gas chromatography (GC) method. The mini-TOFMS exhibited a linear response range from 69 ppmv to 3.0 × 105 ppmv with the limit of detection (LOD, S/N = 3) of 19.0 ppmv. The correlation of GC and mini-TOFMS for Ne quantitative analysis was as high as 0.98. The performance of the newly designed method with the mini-TOFMS was demonstrated by on-site locating the underground natural gas pipeline leakage point in the experimental station. And leakage point of the natural gas pipeline, especially for those pipelines with different gas pressure buried under the same road, can be found more efficiently and accurately.

Failure Analysis on Tube Arm Cylinder Hydraulic Excavator

The Failure on tube rod arm cylinder hydraulic excavator caused to lose production and processing time on mining site. Investigation included visual inspection, chemical analysis, metallography analyze, and microhardness test. Tube material used high silicon material type while the standard used ST52 carbon steel type. The tube was broken and crack to several pieces. The chemical composition of the tube has different in sulfur and silicon content. From hardness test with micro hardness method, sample tube broken has lower hardness compared to standard hardness. Metallography analysis obtained the phase of tube has same phase with standard which is ferrite and pearlite phase but has different grain size. Based on this study, it can be resumed failure on tube is because impurities and different specification on raw material.

Sampler filling time during arterial and venous puncture: An observational study

Introduction: An arterial blood gas (ABG) is a blood test that is performed using blood from an artery. When obtaining an arterial blood sample via percutaneous puncture, there is a risk of accidentally obtaining venous blood. Conventional methods of confirming arterial blood at the bedside such as blood colour and pulsatile return can be misleading in patients with low blood pressure or hypoxaemia. The blood of patients with hypoxaemia can show a dark colour similar to venous blood and patients with low blood pressure may have very low pulsatile action. Aim: The purpose of this study was to determine if the arterial sampler filling time can be an accurate predictor of obtaining arterial blood sample in adults. Methodology: Forty patients were enrolled prospectively who required arterial blood sample or venous sample in medical and surgical intensive care unit. During the arterial and venous puncture procedures the amount of time it took to fill the sample tube was measured with the help of stop watch in s/ml was measured. Results: Twenty patients were in the arterial group and 20 patients in venous group. The mean ± SD filling time was 12 ± 3 s/ml for the arterial group and 112±21 s/ml for the venous group. Conclusion: There is a statistically significant difference between arterial and venous filling times using an arterial blood sampler in human subjects. There is no relationship between mean arterial pressure (MAP) and arterial sampler filling times.

Correct estimation of permeability using experiment and simulation

Estimation of permeability of porous media dates back to Henry Darcy [H. Darcy, Les Fontaines Publiques de la Ville de Dijon (Victor Dalmont, 1856)], and its knowledge is essential in many scientific and engineering endeavors. Despite apparent simplicity of permeability measurements, the literature data are scattered, and this scatter not always can be attributed to the precision of experiment or simulation or to sample variability. Here, we demonstrate an excellent agreement (<1%) between experiments and simulations, where experimental results are extensive and stable, while flow is simulated from first principles, directly on three-dimensional images of the sample, and without fitting parameters. Analyzing when experiments and simulations agree reveals a major flaw affecting many experimental measurements with the out-of-sample placement of pressure ports, including industry standards. The flaw originates from (1) incorrect calculation of the applied pressure gradient, (2) omitting virtual part of the measured system, and (3) pressure loss at the sample–tube contact. Contrary to common wisdom, the relative magnitude of (3) is defined by the sample–tube diameter ratio and is independent of the size of sample pores. Our findings are applicable to a wide range of permeability measurements, including geological-sample-type (Hassler cell) and membrane-type. The reported pressure loss (3) also affects two-phase flow measurements, such as capillary pressure estimation. Removing or taking the flaw into account advances the understanding and control of flow-related processes in complex geometries.

Comparison of C2N Diagnostics’ Aβ40, 42, and 42/40 ratio in Plasma Stored in Micronic and Sarstedt Tubes

AbstractBackgroundVariation in biospecimen collection, processing, and storage parameters can introduce pre‐analytical variables that may confound interpretation of biomarker results. Samples collected under different study protocols or over a long period of time may require different labware, such as storage tubes. Comparability of storage tubes is necessary to better interpretate data collected both longitudinally within studies and across studies that may utilize various labware. The focus of this experiment was to perform comparability studies between plasma biomarkers measured in two polypropylene tube types: Sarstedt tube (72.694.006) and an automation friendly Micronic tube (MP52755).MethodsBlood was collected from healthy controls (N=23) and Alzheimer’s Disease (AD) subjects (N=16) by the Indiana Biobank. Participants’ brain amyloid status was unknown. Plasma from the same subjects was aliquoted (0.5 mL) into both Micronic and Sarstedt polypropylene tubes following standard NCRAD protocols and then frozen and stored at ‐80 °C for <7 months prior to analysis. Blinded samples were thawed once and analyzed for ApoE proteotype, Aβ40 and Aβ42 using liquid chromatography‐high resolution tandem mass spectrometry (LC‐MS/MS; C2N Diagnostics, St. Louis, MO). Data was analyzed in JMP 16.0.0 with the method comparison add‐in and GraphPad PRISM 9.3.1 to determine comparability of the measurements made in the two sample tube types.ResultsComparability analysis found a high correlation of measured Aβ40, Aβ42 and the Aβ42/Aβ40 ratio in plasma stored in Micronic and Sarstedt tubes. Correlation analysis revealed slopes and intercepts within 95% confidence limits of 1 or 0 respectively. Bland Altman analysis showed low measurement bias (4‐7%) between the two tube types. ApoE isoform specific proteotypes were identical between tube types for all subjects.ConclusionResults of the tube type study were within the validated performance range of the measurements. Plasma stored in Micronic and Sarstedt tubes can be used interchangeably when detecting ApoE proteotype and quantifying Aβ40 and Aβ42 concentrations using C2N’s LC‐MS/MS analytical platform. These results support the efforts of large biorepositories, like NCRAD to transition the storage of biospecimens from the larger, less automation friendly Sarstedt tube to the more automation friendly, freezer‐space saving Micronic tube. Supported by U24 AG021886 and UL1TR002529.

Development of a pressure-retaining separation and transfer system for sediment and overlying seawater

Methane leakage at the interface between sediment and overlying seawater is an important basis for gas hydrate exploration. Therefore, a transfer device with working pressure of 30MPa and corresponding scheme are proposed to separate and transfer the sediment and overlying water inside the sampler under the condition of pressure-retaining. Based on the pressure relief valve with adjustable threshold pressure, the device transfers the overlying water by compressing the internal volume and transfers the sediment by secondary sampling. The performance of transfer device is studied by simulation and experiment. Based on the coupled Eulerian-Lagrangian approach in the Abaqus, the secondary sampling was investigated, and the penetration resistance and coring rate of the secondary sampling tube are 141N and 86.2%, respectively. By using the hydraulic simulation software AMESim, the pressure fluctuation caused by the movement of the mechanism during the transfer process was studied, and the pressure fluctuation amplitude is within 0.89 MPa. Furthermore, the laboratory transfer tests were carried out under high pressure conditions, and meantime, the simulation results are verified. Under the working condition of 30MPa, the device can maintain a pressure loss of no more than 8.0% (2.4MPa) within two hours, maintain pressure fluctuations during the transfer process within 4.8% (1.44MPa), and ensure that the pressure in the culture kettle decreases by 4.7% relative to the pressure in the sampler after the transfer, which shows the feasibility of the device application.

A Review of Methods Used to Detect Methamphetamine from Indoor Air and Textiles in Confined Spaces

Methamphetamine manufacture, use, and the resulting contamination is a significant issue that affects public health, the environment, and the economy. Third-hand exposure to methamphetamine can result in adverse health risks for individuals and first responders. Such exposures can result from the inhalation of airborne residues or from contact with contaminated objects. This review was conducted to determine the current methods used for methamphetamine extraction from indoor air and porous fabric materials. Dynamic solid phase microextraction (SPME) and sorbent sampling tubes have been applied to extract airborne methamphetamine residues from contaminated properties. SPME and solvent extraction have been applied to sample clothing and textiles for methamphetamine detection. This review demonstrates that there is limited literature on the detection of methamphetamine from indoor air and clothing. Supplementary and consistent methods to detect methamphetamine from air and porous surfaces should be developed and published to allow better assessment of the environmental risk to public health caused by third-hand exposure to methamphetamine.

The biofilm formation and antibiotic resistance of bacterial profile from endotracheal tube of patients admitted to intensive care unit in southwest of Iran.

Ventilator-associated pneumonia (VAP) is a prevalent nosocomial illness in mechanically ventilated patients. Hence, the aim of this study was to investigate the pattern of antibiotic resistance and biofilm formation of bacterial profiles from Endotracheal Tubes of patients hospitalized in an intensive care unit in southwest Iran. According to the standard operating method, the microbiological laboratory conducts bacteria culture and susceptibility testing on endotracheal Tube samples suspected of carrying a bacterial infection. The Clinical and laboratory standards institute (CLSI) techniques are used to determine the Antimicrobial resistance (AMR) of bacterial isolates to antibiotics using the disk diffusion method. The crystal violet staining method was used to assess the biofilm-forming potential of isolates in a 96-well microtiter plate. In total, (51%) GPBs were included in this study. The isolated GPB were coagulase-negative Staphylococcus (16%), S. aureus (14%). In total, (40%) of GNB were included in this study. The isolated GNB were Klebsiella spp. (36%), A. baumannii (22%), P. aeruginosa (35%). (32%) bacterial strains were MDR and (29%) strains were XDR. The results of biofilm formation showed (72%) were biofilm producers. VAP is a common and severe nosocomial infection in mechanically ventilated patients. Controlling biofilm formation, whether on the ET or in the oropharyngeal cavity, is thus an important technique for treating VAP. Colistin and linezolid are antibiotics that are effective against practically all resistant GNB and GPB isolates.

Research on the evaluation method of lunar soil disturbance based on the fitting of Gaussian surface

It is crucial to maintain the layer sequence information on in situ lunar soil during the lunar soil sampling. In this paper, a discrete element model for direct push sampling of the lunar weathering layer is established, and the relationship between the perturbation rate of the lunar soil layer sequence information and the sampling depth is obtained. A quantitative evaluation method of the perturbation rate of the structural information on the lunar soil layer sequence based on the Gaussian curvature is proposed by reconstructing the center-of-mass point cloud model of the marked layer lunar soil particles in MATLAB. The proposed method can accurately describe the perturbation rate of lunar soil layer sequence information and can analyze the degree of lunar soil disturbance according to the displacement of the sampling tube and mechanical parameters in real-time inversion during the sampling process. When the sampling depth is 40 mm, the minimum and maximum perturbation rates of sampling along the penetration direction of the machine are 5.261 % and 27.649 %, respectively. The perturbation rate shows a trend of first decreasing and then increasing. The method proposed in this study could effectively solve the problem that the disturbance of lunar soil bedding information was difficult to evaluate in the sampling process of lunar regolith.

Optimization of an Adherent Microfluidic Device for Use in Sickle Cell Disease

Background: In sickle cell disease (SCD), a mutation in the beta globin gene results in an abnormal hemoglobin, HbS, which polymerizes under low oxygen conditions. These hemoglobin polymers impact red cell adhesion, deformability, and whole blood viscosity. For thirty years, there was only one widely used SCD modifying agent, hydroxyurea, which could be monitored by conventional laboratory tests. Now, in this era of three new FDA approved drugs for SCD, and several more in the pipeline, as well as gene-based therapy, we need tools to assess the impact of therapies on red cell function and quality. Microfluidics based devices could meet this need, but there is a lack of robust, easy to use, clinically validated microfluidic devices. Here we describe the collaborative development of a laminin lined microfluidics device intended to evaluate the impact of SCD modifying therapies on red cell adhesion to the microvasculature. Early versions of the device were limited in function due to flawed device design and an inadequate hematocrit and BSA concentration. Prior to optimization, the sample and wash lines shared a single inlet port. The current device separates the two, keeping the wash port independent and permitting a clean wash post sample perfusion. Samples used in development were unaltered; Patient samples were introduced early in development to direct optimization. Methods: Samples were collected into EDTA coated tubes and stored at 4 degrees C. Samples were spun in a centrifuge at 200g for 15 minutes at 4 degrees C. Plasma and buffy coat layers were removed via aspiration. 500ul of 1X PBS was added to each tube. Devices were fabricated using polydimethylsiloxane (PDMS). After pouring individual devices, the mold was placed into a desiccator for 1 hour and cured at 60 degrees C overnight. Devices were diced and permanently bonded to seal the microchannels. Devices were stored in a 60 degree C oven. 100ug/ml solution of Human Placental Laminin was prepared. 20ul of laminin was applied to each channel and incubated overnight at 4 degrees C. 25ul of Bovine Serum Albumin was applied to each channel and incubated at room temperature for 2 hours. Channels were washed with 1x PBS. Samples were transferred to a 1mL syringe; A pre-assembled needle tip with tubing was added to the syringe. Sample tubing was connected to the appropriate inlet port. To visualize adhesion, the device was mounted on top of an inverted bright-field microscope. Harvard Apparatus syringe pump was used to perfuse samples and wash at the relevant flow rate. Channels were imaged at 20x magnification. Images were taken at the same ROI and adhered cells were counted manually and using proprietary cell quantification software. Figure 1: Measurements for adhered RBC and sRBC at sequential stages of development. (a)HbAA and HbSS adhesion captured in current adhesion device (p-value=0.0358) (N=8); (b); HbAA and HbSS adhesion captured at 20% hct. (c) HbAA and HbSS adhesion captured at BSA concentrations. No BSA: (p-value=0.001) (N=24) | 1.5% BSA: (p-value< 0.0001) (N=57) Conclusion: With use of our robust adhesion device, sRBC function and its correction can be monitored pre-therapy and throughout treatment; Then, make selection of the appropriate second agent based on individual need and drug effect. Our results indicate clear improvements from the prototype to the current version, achieving genotype discrimination with significant difference (p = 0.0358). Due to a limited sample size, results at 20% hct were not significantly different. Under no BSA, separation between HbAA and HbSS was achieved with significance, but an undesirable overlap between the two encouraged continued concentration testing. 2% BSA extensively diminished adhesion among sRBC, reducing adherence to near RBC levels. 1.5% BSA afforded an ideal adhesion range for both HbAA and HbSS (p<0.0001). Rather than using glyceraldehyde modified RBCs, we incorporated fresh patient samples into the development process to more suitably analyze RBC adherence. With no intent to replicate in vivo conditions, our device was constructed to analyze red cell changes on an individual level. We propose a functional adhesion assay to produce biomarkers that will correlate with SCD clinical course. With analytical and clinical validation, our microfluidic assay can capture functional changes to RBCs and provide objective, quantitative biomarkers of pain events for use in clinical trials and in patient care Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

A method for collecting high numbers of blood samples in standard vacuum tubes from non-heparinized pigs.

Large animal models allow for collection of substantial amounts of biological material. However, the collection of larger volumes (>100 ml) of blood from pigs can be a challenge: (i) the peripheral veins are not suitable for collection of high numbers of standard blood tubes as the veins tend to collapse; and (ii) the alternative option of cannulating deeper veins mandates surgical exposure of the vessels and often the need for heparinization, which is undesirable for some blood analysis. During an immunization trial in 40 pigs, we assessed the femoral and saphenous arteries as practical vessels for collecting 250 ml of blood from each pig in standard collection tubes without heparinization. Blood collected from the saphenous artery by a standard butterfly needle proved particularly useful and 250 ml blood could be collected successfully in 24 of 25 pigs by this approach.

Improvements on the Diagnostic Residual Gas Analyzer at Wendelstein 7-X

Exhaust gas analysis provides key information on fusion processes, divertor operation, and wall state in fusion experiments and future reactors. The diagnostic residual gas analyzer (DRGA) concept has been developed for ITER with a focus on fast helium and hydrogen isotope detection. The first operation of the prototype DRGA (P-DRGA) at the stellarator Wendelstein 7-X showed potential for improvement in terms of magnetic sensor shielding, data acquisition automation, and potential new additions to the cluster of sensors on the P-DRGA. More recently, a Monte Carlo simulation of the flow of the mixed gas species effluent from the pressure-reducing orifice, down to about 8-m sampling tube and into the analysis region of the sensors, has been found to generally agree with previous calculations and measurements but revealed potential back-streaming effects for light gases, with impact on detection limits both for the prototype and for the ITER DRGA currently in design. For the upcoming campaign of the prototype, an enhanced soft iron shield will safeguard the gauges against magnetic stray field influence. The newly introduced shielding has been tested for its effect on magnetic stray fields and found to reduce the inside residual field by about two orders of magnitude.